North Korean leader Kim Jong Un praised the legacy of the Workers’ Party of Korea ahead of its 80th anniversary, as delegations from China, Russia, and Vietnam arrived in Pyongyang for celebrations.

Chinese Premier Li Qiang, Russian delegation led by former President Dmitry Medvedev, and Vietnam’s Communist Party chief To Lam attended, with Lam’s visit marking the first by a Vietnamese party leader in nearly 20 years.

Kim toured the Party Founding Museum and delivered a speech honoring the party’s founders, including his grandfather Kim Il Sung, calling for the current generation to uphold revolutionary duties and maintain the party’s ideological purity.

The anniversary comes shortly after Kim appeared with Xi Jinping and Vladimir Putin at a Beijing parade commemorating the end of World War II, reinforcing his diplomatic ties, Reuters has reported.

South Korean officials have noted signs that North Korea may also hold a military parade this week to mark the historic milestone.